Metallic filling materials



Patented July 21, 1936 PATENT OFFICE METALLIC FILLING MATERIALS Walter Wyss, Arbon, Switzerland, assignor to Socit Anonyme Adolphe Saul-er, Arbon, Switzerland No Drawing.

Serial No. 52,071. 1934 1 Claim.

5 low melting point and to be kneadable at least to an appreciable extent during the period of hardening, thus between their melting and hardening points. Furthermore, the filling material must be acid-proof and have a certain amount of strength.

Hitherto alloys were used as filling materials which were composed of about 75% of lead and of tin. Such an alloy comes up to the said requirements, but the surface of the filling material 5 inserted in the cavity needs to be worked with file and brush. From these operations dust of finely divided metal particles arises which, due to its lead content, is detrimental to the health of the men occupied with this work. This dust can 720 be removed by suction action by special auxiliary apparatus, but the application of such means, apart from being expensive, hampers the working of the filling material.

According to the present invention, these draw- Application November 29, 1935, In Germany October 30,

backs are eliminated while at the same time the above-mentioned requirements are satisfied by providing a filling material which consists in an alloy which is composed substantially of cadmium and tin. Advantageously the alloy is composed of about parts by weight of cadmium and 15 parts of tin. Due to the absence of lead this alloy has no detrimental effect on the health of the men working it with file and brush. Furthermore, this alloy is kneadable during the period of hardening and presents the required resistivity against acids, as well as strength. Moreover, this filling material can be worked in the same convenient manner as the insalubrious lead containing alloy hitherto used.

Naturally, also metals such as zinc, bismuth and so forth may be admixed to the alloy, but only in such amounts that the characteristic properties of the alloy are preserved.

What I claim is:

A metallic filling material consisting in an alloy comprising 85 percent of cadmium and 15 per cent of tin.

WALTER WYSS. 

